#include <fcntl.h>
#include <stdio.h>
int main()
{
  int fd;
  int val;
  printf("Please input a number:");
  scanf("%d", &val);
  fd = open("/dev/hellodev", O_RDWR);
  if (fd < 0)
  {
    printf("Can`t open!\n");
  }
	write(fd, &val, 2);
	read(fd,&val,2);
  return 0;
}
